BELIZE CITY -- Fertilizer and sediment runoff from sugarcane, banana and pineapple plantations are threatening tourism by damaging a coral reef stretching along the Caribbean coasts of Mexico, Belize, Guatemala and Honduras, according to a report released on Tuesday.

The report by the World Resources Institute and other groups said that reducing pesticides, fertilizers and erosion could help head off increasing damage to the world's second-largest barrier reef, which stretches over 600 miles.

The report estimates that over 80 percent of the sediment and over half of all nutrients that damage the reefs originate in Honduras, whose large rivers drain into the Caribbean.

"Our analysis shows that pollution from farms in Honduras can inadvertently damage the entire Mesoamerican reef, which is an important source of revenue from tourism and fisheries," said Lauretta Burke, an expert in coastal ecosystems for the resources institute and one of the authors of the report.

Silt runoff can cloud water, cutting off coral species' access to sunlight. Pesticides can kill coral, and fertilizers such as nitrogen and phosphorous can spur the growth of algae, which competes with coral for sunlight. The study estimates that, if current practices continue, silt runoff may increase by as much as 13 percent by 2025.

Other studies have estimated that up to 30 percent of the world's coral reefs have died in the last 50 years, and another 30 percent are severely damaged, often as a result of sedimentation and rising sea temperatures.

Liza Karina Agudelo, coordinator of the International Coral Reef Action Network-MesoAmerican Reef Alliance, said the study doesn't intend to cast blame on Honduras, whose rain and drainage patterns make it vulnerable to runoff, but rather "sends the message to everyone that the reef belongs to the whole region. It doesn't help to blame one country."

For centuries, huge plantations of sugar cane, pineapples and bananas were the region's main source of wealth. In recent years, tourism and remittances sent home by migrants working abroad have since replaced those crops as the main source of outside income for many of the region's countries.

Groups including the World Wildlife Fund are now working with planters and farmers in Honduras to improve farming practices.

"We are using the results of the study to reduce the use of pesticides and to control erosion of soil from important agricultural sectors" in Honduras and elsewhere, said Jose Vasquez, head of the WWF's agriculture office in Central America.

Vasquez said his group is now working with big growers as well as citrus and sugar cane growers in Honduras.

More than 80 percent of the sediment and 50 percent of the pollutants entering the coastal waters of the Mesoamerican Barrier Reef originate from human activities in nearby mountainous Honduras, according to the World Resources Institute (WRI), in an analysis unveiled here today at a press conference.

The analysis is the first to determine the origin and volume of sediment and pollution that run off agricultural lands, via the region's vast river networks, into the neighboring Gulf of Honduras and Caribbean Sea. The waters are home to the Mesoamerican Barrier Reef - the largest coral reef system in the Western Hemisphere, stretching for more than 600 miles, and shared by Belize, Guatemala, Honduras and Mexico.

"As humans have altered the landscape, an increasing amount of sediment and nutrients are reaching coastal waters and the Mesoamerican Barrier Reef itself," said Lauretta Burke, a senior coastal ecosystem expert at WRI and co-author of the study. "Our analysis shows that pollution from farms in Honduras can inadvertently damage the entire Mesoamerican reef, which provides an important source of revenue from tourism and fisheries."

To link their findings to action on the ground, Burke and co-author Zachary Sugg performed Watershed Analysis for the Mesoamerican Reef - released today on CD-ROM and online - as part of a project under the International Coral Reef Action Network (ICRAN) Mesoamerican Reef Alliance, and with contributions from the United Nations Environment Program's World Conservation Monitoring Centre. The ICRAN-MAR Alliance works to diminish the impacts to the Mesoamerican Reef by promoting best management practices in tourism, fisheries and watershed management.

Another partner in the Alliance, the World Wildlife Fund (WWF), is using WRI's analysis to identify agricultural areas in the region that need to reduce pesticide use and soil erosion, and is setting up collaboration agreements with farmers and agricultural businesses to help them implement management practices that reduce impacts on the reef.

"We are using the analysis results to reduce pesticides and to control soil erosion from major commercial agricultural sectors while sustaining productivity," said José Vásquez, a senior agriculture official for WWF Central America. "At present, WWF is partnering with agroindustries such as Chiquita; Dole; CropLife Latin America; The Association of Citrus Producers from Sonaguera, Honduras (ACISON); and Azucarera del Norte, S. A. (AZUNOSA), one of the major sugarcane producers of Northern Honduras."

On December 5, AZUNOSA signed a memorandum of understanding with WWF. AZUNOSA's general manager, engineer Mario Hernández, voiced his company's commitment to quick results, adding, "The most effective and responsible way of doing business is by contributing to the society in which we operate, creating job opportunities, taxes for public services, and protecting the environment. Working with WWF will be a beneficial experience for Honduras and for our region."

WRI's Burke added, "Our results show that investments in these types of efforts are likely to be worth it in the long term. Based on our simulation, we see reductions in sediment and pollutant runoff if better land management practices are implemented."

Other key findings within the analysis include:

* Along with more than 80 percent of sediment, more than half of all nutrients (both nitrogen and phosphorous) originate in Honduras.* Guatemala was identified as a source of about one-sixth of all sediments and about one-quarter of all nitrogen and phosphorous entering coastal waters along the Mesoamerican reef.* Compared to the other countries, relatively minor percentages of the regional sediment load come from Belize and the Yucatan Peninsula in Mexico. Belize contributes between 10 to 15 percent of nutrients and Mexico is estimated to contribute about 5 percent of the nutrients from all modeled watersheds.* Of the 400 watersheds in the region, the Ulua watershed in Honduras was found to be the largest contributor of sediment, nitrogen, and phosphorous. Other large rivers found to be significant contributors of sediment and nutrients are the Patuca (in Honduras), Motagua (in Guatemala and Honduras), Aguan (in Honduras), Dulce (in Guatemala), Belize (in Belize), and Tinto o Negro (in Honduras).* Under land-use scenarios which favor free markets and little policy regarding the environment, nutrient delivery is likely to increase by about 10 percent by 2025, while sediment delivery might increase by 13 percent or more.* If environmental policies that favor sustainable development are implemented, nutrient and sediment delivery are likely to be reduced by at least 5% from current levels, promoting recovery of degraded corals.

it looks incredibly small from the helicopters. you can see nearly 270 degrees, can see from both out past the reef to land very easily. without turning your head. riding in the chopper the space between the island and the mainland got real small for me.